Display device

ABSTRACT

A display device includes a display substrate including: a pixel area provided in plurality separated from each other, and a plurality of through holes separated from each other; a light-emitting diode provided in plurality on the display substrate arranged in the pixel areas thereof; and a wiring line provided in plurality on the display substrate, the wiring line including a first wiring line and a second wiring line which are each electrically connected to the light-emitting diode.

This application is a continuation application of U.S. application Ser.No. 16/218,642 filed Dec. 13, 2018 and issued as U.S. Pat. No.10,847,696 on Nov. 24, 2020, which is a divisional application of U.S.application Ser. No. 15/488,902 filed Apr. 17, 2017 and issued as U.S.Pat. No. 10,186,648 on Jan. 22, 2019, which claims priority to KoreanPatent Application No. 10-2016-0046493, filed on Apr. 15, 2016, and allthe benefits accruing therefrom under 35 U.S.C. § 119, the contents ofwhich in their entirety are herein incorporated by reference.

BACKGROUND 1. Field

One or more embodiments relate to a display device.

2. Description of the Related Art

A light-emitting diode (“LED”) is a semiconductor device in which when avoltage is applied to a P-N diode of the LED in a forward direction, ahole and an electron are injected then recombined, and energy generatedby recombination of the hole and the electron is converted to lightenergy.

The LED may be used for mobile apparatuses such as smart phones, lap-topcomputers, digital cameras, camcorders, personal digital assistants(“PDA”s), tablet personal computers (“PC”s), watches, or electronicapparatuses such as desk-top computers, televisions, outdoor billboards,display devices for exhibition, dashboards for automobiles, and head updisplays (“HUD”s).

SUMMARY

One or more embodiments include a display device in which alight-emitting diode is relatively easily connected to a wiring line.

According to one or more embodiments, a display device includes: adisplay substrate including: a pixel area provided in pluralityseparated from each other, and a plurality of through holes separatedfrom each other; a light-emitting diode provided in plurality arrangedon the display substrate in the pixel areas thereof; and a wiring lineprovided in plurality on the display substrate including a first wiringline and a second wiring line which are each electrically connected tothe light-emitting diode.

Each light-emitting diode may include at least one first contactelectrode, at least one second contact electrode, and a p-n diodebetween the at least one first contact electrode and the at least onesecond contact electrode, the at least one first contact electrode beingelectrically connected to the first wiring line, and the at least onesecond contact electrode being electrically connected to the secondwiring line.

The first wiring line and the second wiring line may be arranged indifferent layers on the display substrate and cross each other.

For a same light-emitting diode to which the first and second wiringlines are connected, the first wiring line and the light-emitting diodemay form a first contact point in at least two first regions of thelight-emitting diode, and the second wiring line and the light-emittingdiode may form a second contact point in at least two second regions ofthe light-emitting diode different from the first regions.

The first wiring line may include a curve and lengthwise extend overpixel areas arranged in a first direction of the display substrate, andthe second wiring line may include a curve and lengthwise extend overpixel areas arranged in a second direction of the display substratewhich crosses the first direction.

In a top plan view, the first wiring line may lengthwise extend as azigzag type line over pixel areas arranged in a first direction of thedisplay substrate, and the second wiring line may lengthwise extend as azigzag type line over pixel areas arranged in a second direction of thedisplay substrate which crosses the first direction.

The display device may further include insulating layers alternated withthe first wiring line and the second wiring line in a thicknessdirection of the display substrate, and contact holes defined spacedapart from each other in the insulating layers. The first wiring lineand the second wiring line may be respectively electrically connected tothe at least one first contact electrode and the at least one secondcontact electrode, via the contact holes in the insulating layers.

The first wiring line and the second wiring line in different layers onthe display substrate define a height difference therebetween, and asame light-emitting diode to which the first and second wiring lines areconnected may have a step difference corresponding to the heightdifference between the first wiring line and the second wiring line.

The at least one first contact electrode and the at least one secondcontact electrode may each be disposed at a bottom of the p-n diodewhich faces the display substrate, and the bottom of the p-n diode maydefine the step difference corresponding to the height differencebetween the first wiring line and the second wiring line.

The insulating layers may include: a first insulating layer between thefirst wiring line and the second wiring line, and a second insulatinglayer between the second wiring line and the light-emitting diode. Thefirst wiring line may be electrically connected to the first contactelectrode via a first contact hole in the first and second insulatinglayers, and the second wiring line may be electrically connected to thesecond contact electrode via a second contact hole in the secondinsulating layer.

The display device may further include: a barrier layer in the pixelareas, the barrier layer being between the display substrate and thefirst wiring line which are respectively in the pixel areas.

The display device may further include an individual sealing layerrespectively on each of the light-emitting diodes arranged in the pixelareas.

A length of the wiring line may extend in one direction of the displaysubstrate and may include arranged along the length thereof: a planarportion provided in plurality respectively contacting the displaysubstrate, and a curved portion which connects adjacent planar portionsto each other.

The curved portion may protrude from an end of each of the adjacentplanar portions to be spaced apart from the display substrate in athickness direction of the display substrate.

The curved portion may be provided in plurality alternating with theplurality of planar portions, and each of the light-emitting diodesarranged in the pixel areas.

The first wiring line may include a first planar portion provided inplurality and a first curved portion connecting adjacent first planarportions to each other, and the second wiring line may include a secondplanar portion provided in plurality and a second curved portionconnecting adjacent second planar portions to each other. For a samelight-emitting diode to which the first and second wiring lines areconnected, the first curved portion may be electrically connected to thefirst contact electrode of the light-emitting diode, and the secondcurved portion may be electrically connected to the second contactelectrode of the light-emitting diode.

The display substrate may further include an island region provided inplurality spaced apart from each other along the display substrate andat which the wiring line contacts the display substrate, and the firstplanar portion of the first wiring line and the second planar portion ofthe second wiring line may be respectively bonded to the island regionsof the display substrate.

The display substrate may be bendable, curvable or rollable along adirection, each of the plurality of through holes may pass through athickness the display substrate, and in a top plan view of the displaysubstrate, each of the through holes may have a length which extends inthe direction in which the display substrate is bendable, curvable orrollable.

In the top plan view: each of the plurality of through holes may definea width perpendicular to the length thereof and opposing ends thereofalong the length thereof, and the width of each through hole at both ofthe opposing ends thereof may be greater than at remaining portionsthereof.

The first wiring line and the second wiring may be respectively appliedwith electric signals, and for a same light-emitting diode to which thefirst and second wiring lines are connected, the light-emitting diodemay be applied with the electrical signals and emit light.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other features will become apparent and more readilyappreciated from the following description of the embodiments, taken inconjunction with the accompanying drawings in which:

FIG. 1 is a perspective view of an embodiment of a display deviceaccording to the invention;

FIG. 2 is an enlarged top plan view of portion A of FIG. 1;

FIG. 3 is an enlarged top plan view of portion B of FIG. 2;

FIG. 4 is a cross-sectional view of an embodiment of one pixel area of adisplay device according to the invention;

FIG. 5 is an enlarged top plan view of another embodiment of portion Aof the display device in FIG. 1 according to the invention;

FIG. 6 is an enlarged top plan view of an embodiment of a region of adisplay substrate of a display device according to the invention;

FIG. 7 is an exploded perspective view of a wiring line and alight-emitting diode (“LED”) in an island area of FIG. 6;

FIG. 8 is a cross-sectional view illustrating an embodiment of aconnection between the wiring line and the LED of FIG. 7; and

FIGS. 9A to 9D are cross-sectional views sequentially illustrating anembodiment of a process of manufacturing a wiring line including acurved portion according to the invention.

DETAILED DESCRIPTION

As the present disclosure allows for various changes and numerousembodiments, exemplary embodiments will be illustrated in the drawingsand described in detail in the written description. An effect and acharacteristic of the present disclosure, and a method of accomplishingthese will be apparent when referring to embodiments described withreference to the drawings. This present disclosure may, however, beembodied in many different forms and should not be construed as limitedto the exemplary embodiments set forth herein.

Hereinafter, the present disclosure will be described more fully withreference to the accompanying drawings, in which exemplary embodimentsof the present disclosure are shown. When description is made withreference to the drawings, like reference numerals in the drawingsdenote like or corresponding elements, and repeated description thereofwill be omitted.

It will be understood that when a layer, region, or component isreferred to as being “on,” another layer, region, or component, it canbe directly or indirectly on the other layer, region, or component. Thatis, for example, intervening layers, regions, or components may bepresent. Sizes of elements in the drawings may be exaggerated forconvenience of explanation. In other words, since sizes and thicknessesof components in the drawings are arbitrarily illustrated forconvenience of explanation, the following embodiments are not limitedthereto. As used herein, one element described as “connected” to asecond element may be in physical and/or electrical connection with thesecond element.

in the following examples, the x-axis, the y-axis and the z-axis are notlimited to three axes of the rectangular coordinate system, and may beinterpreted in a broader sense. For example, the x-axis, the y-axis, andthe z-axis may be perpendicular to one another, or may representdifferent directions that are not perpendicular to one another.

It will be understood that, although the terms “first,” “second,”“third” etc. may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are only used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, “a first element,” “component,” “region,” “layer” or“section” discussed below could be termed a second element, component,region, layer or section without departing from the teachings herein.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a,” “an,” and “the” are intended to include the pluralforms, including “at least one,” unless the content clearly indicatesotherwise. “At least one” is not to be construed as limiting “a” or“an.” “Or” means “and/or.” As used herein, the term “and/or” includesany and all combinations of one or more of the associated listed items.It will be further understood that the terms “comprises” and/or“comprising,” or “includes” and/or “including” when used in thisspecification, specify the presence of stated features, regions,integers, steps, operations, elements, and/or components, but do notpreclude the presence or addition of one or more other features,regions, integers, steps, operations, elements, components, and/orgroups thereof.

Furthermore, relative terms, such as “lower” or “bottom” and “upper” or“top,” may be used herein to describe one element's relationship toanother element as illustrated in the Figures. It will be understoodthat relative terms are intended to encompass different orientations ofthe device in addition to the orientation depicted in the Figures. Forexample, if the device in one of the figures is turned over, elementsdescribed as being on the “lower” side of other elements would then beoriented on “upper” sides of the other elements. The exemplary term“lower,” can therefore, encompasses both an orientation of “lower” and“upper,” depending on the particular orientation of the figure.Similarly, if the device in one of the figures is turned over, elementsdescribed as “below” or “beneath” other elements would then be oriented“above” the other elements. The exemplary terms “below” or “beneath”can, therefore, encompass both an orientation of above and below.

Unless otherwise defined, all terms (including technical and scientificterms) used herein have the same meaning as commonly understood by oneof ordinary skill in the art to which this disclosure belongs. It willbe further understood that terms, such as those defined in commonly useddictionaries, should be interpreted as having a meaning that isconsistent with their meaning in the context of the relevant art and thepresent disclosure, and will not be interpreted in an idealized oroverly formal sense unless expressly so defined herein.

Hereinafter, a display device according to an embodiment will bedescribed more fully with reference to the accompanying drawings, inwhich embodiments of the present disclosure are shown. When descriptionis made with reference to the drawings, like reference numerals in thedrawings denote like or corresponding elements, and repeated descriptionthereof will be omitted.

FIG. 1 is a perspective view of an embodiment of a display device 100according to the invention.

Referring to FIG. 1, the display device 100 includes a display panel 110which generates and displays an image at a viewing side of the displaydevice 100. The display panel 110 may be a flexible panel.

The display panel 110 includes an active area AA at which the image isgenerated and displayed and an inactive area IAA extending from outeredges of the display panel 110 to the outside of the active area AA. Inan embodiment, the inactive area IAA surrounds the active area AA in thetop plan view.

FIG. 2 is an enlarged top plan view of portion A of the display panel110 of FIG. 1.

Referring to FIG. 2, a pixel area PA provided in plurality may bedefined or disposed on a display substrate 201 of the display panel 110.The display substrate 201 may be one of a flexible glass substrate and aflexible polymer substrate. The display substrate 201 may betransparent, semi-transparent or opaque.

The pixel areas PA may be spaced apart from each other by apredetermined interval in the active area AA (see FIG. 1) of the displaysubstrate 201. A light-emitting element such as a light-emitting diode(“LED”) may be disposed on the display substrate 201 in the pixel areaPA thereof to generate and emit light. A separation area SA may bebetween adjacent pixel areas PA.

The separation area SA includes a first separation area SA1 defining alength thereof extending in an X-direction and a second separation areaSA2 defining a length thereof extending in a Y-direction. The length ofthe respective separation areas is larger than a width thereof. TheX-direction may cross the Y-direction. The first separation area SA1 mayseparate a plurality of pixel areas PA arranged in the Y-direction, andthe second separation area SA2 may separate a plurality of pixel areasPA arranged in the X-direction.

A plurality of through holes 202 may be in the separation area SA. Thethrough holes 202 may each pass through the display substrate 201, suchas completely through a thickness of the display substrate 201 taken ina Z-direction which is perpendicular to both the X-direction andY-direction.

The display panel 110 may be bent, curved or rolled in a direction, suchas in the X-direction or the Y-direction indicated in FIG. 1, but notbeing limited thereto. The display panel 110 (and consequently thedisplay device 100 may be bent, curved or rolled in a diagonal directionincluding both the X-direction and the Y-direction simultaneously. Thethrough holes 202 may extend in a direction in which the displaysubstrate 201 is bent, curved or rolled. In an embodiment, the throughholes 202 may define a shape thereof in the top plan view having alength with is larger than a width, such that the through holes 202 hasa shape which extends long in the separation area SA.

The plurality of through holes 202 collectively includes a first throughhole 203 in the first separation area SA1 and a second through hole 204in the second separation area SA2. The first and second through holes203 and 204 may be provided in plurality within the separation area SA.In an embodiment of manufacturing the display device 100, the throughholes 202 may be formed by laser drilling, but not being limitedthereto.

Since the through holes 202 are in the separation area SA of the displaysubstrate 201 which separates adjacent pixel areas PA thereof,transformation of the display substrate 201, for example, bending,curving and rolling of the display substrate 201 may be relativelyeasily performed. In other words, where the display device 100 (seeFIG. 1) to which the display substrate 201 is applied is used as astretchable display device, the display device 100 may have relativelyhigh flexibility and reduce abnormal transformation owing to the reducedvolume of the display substrate 201 by the material thereof being absentat positions of the through holes 202.

Furthermore, since a plurality of through holes 202 are extendedcompletely through a thickness of the display substrate 201, an overallweight of the display substrate 201 may be reduced since material of thedisplay substrate 201 is absent at the through holes 202. Therefore, theflexibility of the display substrate 201 may improve.

FIG. 3 is an enlarged top plan view of portion B of FIG. 2.

Referring to FIG. 3, an LED 301 may be in the pixel area PA. The LED 301may be provided in plurality within the active area AA. In anembodiment, the LED 301 may generate and emit light of a predeterminedwavelength within a wavelength range from an ultraviolet (“UV”) lightray to visible light. The LED 301 may be a micro LED. In an embodiment,the LED 301 may include at least one of a red LED, a green LED, a blueLED, a white LED and a UV LED.

A plurality of wiring lines 310 may be disposed on the display substrate201. The wiring lines 310 may not overlap through holes 203 and 204which are defined in the display substrate 201.

The wiring lines 310 may be electrically connected to one or more of theLED 301 in the active area AA. The display device 100 may be driven by apassive matrix (“PM”) method to generate and display the image. In anembodiment, for example, since the LED 301 is a micro LED, the LED 301may have a relatively high speed response. Therefore, the display device100 may be driven by the PM method having a relatively simple structure.In another embodiment, the display device 100 may be driven by an activematrix (“AM”) method to generate and display the image.

The wiring lines 310 collectively include a first wiring line 311 and asecond wiring line 312. The first wiring line 311 and the second wiringline 312 may be disposed on and/or on different insulating layers (notshown) of the display panel 110, such that the first and second wiringlines 311 and 312 are insulated from each other. The LED 301 may emitlight when electric signals applied to the first wiring line 311 and thesecond wiring line 312, respectively, are further applied to the LED301. Each of the first and second wiring lines 311 and 312 may define alength thereof which is larger than a width thereof. The width of thewiring line may be taken in a direction normal to an extension directionof the length thereof at a particular point of the wiring line.

The length of the first wiring line 311 may extend over a plurality ofpixel areas PA which are spaced apart in the X-direction of the displaysubstrate 201. The length of the first wiring line 311 may have at leasta curve in the top plan view. In an embodiment, the first wiring line311 may be a curved type line. The first wiring line 311 and/or thesecond wiring line 312 may be defined by an entirely planar portionwhich is not spaced apart from an underlying layer in a thicknessdirection of the display device, but the invention is not limitedthereto.

The length of the second wiring line 312 may extend over a plurality ofpixel areas PA which are spaced apart in the Y-direction of the displaysubstrate 201. Like the first wiring line 311, the second wiring line312 may be a curved type line.

The first wiring line 311 may cross the second wiring line 312 in thetop plan view. In an embodiment, the first wiring line 311 may cross thesecond wiring line 312 in a region in which the LED 301 is arranged. Inan embodiment, a crossing point of the first and second wiring lines 311and 312 may overlap the LED 301.

Specifically, the length of the first wiring line 311 may extend acrossthe LED 301 from a first corner 301 a of the LED 301 to a third corner301 c, which is located in the diagonal direction relative to the firstcorner 301 a. The length of the second wiring line 312 may extend acrossthe LED 301 from a second corner 301 b to a fourth corner 301 d, whichis located in the diagonal direction relative to the second corner 301b. The first wiring line 311 may cross the second wiring line 312 in thecentral region of the LED 301, but is not limited thereto.

To improve a contact characteristic therebetween, the LED 301 may beelectrically connected to the wiring lines 310 in at least two regions.In an embodiment, for example, the LED 301 and the first wiring line 311may form a first contact point 321 in plurality respectively at thefirst corner 301 a and the third corner 301 c. The LED 301 and thesecond wiring line 312 may form a second contact point 322 in pluralityrespectively at the second corner 301 b and the fourth corner 301 d.

A sealing layer 205 may be disposed over the display substrate 201. Thesealing layer 205 includes at least one inorganic layer. In anembodiment of manufacturing the display device 100, the sealing layer205 may be formed by an inkjet process. In an embodiment, the sealinglayer 205 as a discrete element may individually cover a single LED 301disposed in each pixel area PA. In another embodiment, a single sealinglayer 205 may cover adjacent pixel areas PA simultaneously so as to becommonly covering more than one LED 301 across the adjacent pixel areasPA.

In an embodiment, the first wiring line 311 and the second wiring line312 may be in or on different insulating layers among layers of thedisplay device 100 which area disposed on the display substrate 201. Thelayers of the display device 100 are disposed in the Z-direction (e.g.,vertical or thickness direction) of the display device 100.

FIG. 4 is a cross-sectional view of an embodiment of one pixel area PAof a display device 400 according to the invention.

Referring to FIG. 4, the display device 400 includes a display substrate401 (refer to 201 of FIG. 2) on which layers of the display device 400are disposed. The display substrate 401 may include a flexible material.

A first wiring line 402 (refer to 311 in FIG. 3) may be on the displaysubstrate 401. The length of the first wiring line 402 may extend overpixel areas PA spaced apart from each other in one direction of thedisplay substrate 401. In FIG. 4, the length of the first wiring line402 extends in the horizontal (e.g., left-to-right) direction of thedisplay substrate 401.

A barrier layer 403 may be between the display substrate 401 and thefirst wiring line 402. The barrier layer 403 includes at least oneinorganic layer. The barrier layer 403 may be in a region correspondingto each pixel area PA. A region of the display substrate 401 at whichthe barrier layer 403 is not arranged may be relatively easily bentowing to the absence of the barrier layer 403 at that region.

A first insulating layer 404 may be on the first wiring line 402. Thefirst insulating layer 404 covers the first wiring line 402.

A second wiring line 405 (refer to 312 in FIG. 4) may be on the firstinsulating layer 404. The length of the second wiring line 405 mayextend over pixel areas PA spaced apart from each other in anotherdirection of the display substrate 401. In FIG. 4, the length of thesecond wiring line 405 extends into the page.

The first wiring line 402 may cross the second wiring line 405. Thelength directions of the first and second wiring lines 402 and 405 crosseach other, such as the X-direction and Y-direction cross each other(refer to FIG. 1).

A second insulating layer 406 may be on the second wiring line 405. Thesecond insulating layer 406 covers the second wiring line 405.

As described above, the first wiring line 402, the first insulatinglayer 404, the second wiring line 405 and the second insulating layer406 may be stacked in the vertical (e.g., thickness) direction of thedisplay substrate 401. Referring to FIGS. 1 and 4, the thicknessdirection is indicated in the Z-direction.

An LED 410 (refer to 301 in FIG. 4) may be in the pixel area PA.

The LED 410 includes a first contact electrode 411, a second contactelectrode 412, and a p-n diode 413 between the first and second contactelectrodes 411 and 412.

The first and second contact electrodes 411 and 412 may includeconductive paste or a conductive ball.

The p-n diode 413 includes a lower p-doped layer 414, an upper n-dopedlayer 415, and at least one quantum well layer 416 between the p-dopedlayer 414 and the n-doped layer 415. In an embodiment, the upper dopedlayer 415 may be a p-doped layer, and the lower doped layer 414 may bean n-doped layer.

The LED 410 may have various structures.

In an embodiment, the LED 410 may be a horizontal LED. In the horizontalLED, both the first and second contact electrodes 411 and 412 may facethe same direction relative to the p-n diode 413. Specifically, thefirst and second contact electrodes 411 and 412 may both be arrangedtoward the display substrate 401 among sides of the LED 410.

In another embodiment, the LED 410 may be a vertical LED in which thefirst and second contact electrodes 411 and 412 are respectively locatedabove and under the p-n diode 413 in a thickness direction of the LED410.

In another embodiment, the first and second contact electrodes 411 and412 may be respectively provided as a plurality of first and secondcontact electrodes in the horizontal direction or in the verticaldirection of a single LED 401.

The first wiring line 402 and the second wiring line 405 may be indifferent layers of the display device 400 among layers thereof arrangedin the vertical (e.g., thickness) direction of the display substrate401. The first wiring line 402 may be electrically connected to thefirst contact electrode 411 at a first contact hole 407 defined in thefirst and second insulating layers 404 and 406. In an embodiment ofmanufacturing the display device 400, the first contact hole 407 may beformed by removing a portion of the first insulating layer 404 and aportion of the second insulating layer 406 each at a location of thefirst contact hole 407. The second wiring line 405 may be electricallyconnected to the second contact electrode 412 at a second contact hole408 defined in the second insulating layer 406. In an embodiment ofmanufacturing the display device 400, the second contact hole 408 may beformed by removing a portion of the second insulating layer 406 at alocation of the second contact hole 408.

Since the first and second wiring lines 402 and 405 have a heightdifference in the thickness direction, a connection of the first contactelectrode 411 to the first wiring line 402, and a connection of thesecond contact electrode 412 to the second wiring line 405 may berelatively difficult. To facilitate the connections between theseelements, the LED 410 may have a structure defining a step difference inthe thickness direction corresponding to the height difference betweenthe first wiring line 402 and the second wiring line 405. A distance inthe thickness direction from an uppermost surface of the first wiringline 402 to a common reference such as the display substrate 401, may besmaller than that from an uppermost surface of the second wiring line405 to define the height difference.

Specifically, the first contact electrode 411 may be disposed under thelower p-doped layer 414. In an embodiment of manufacturing the displaydevice, material layers for forming the lower p-doped layer 414 and thequantum well layer 416 may be initially disposed overlapping a wholesurface of a material layer for forming the upper n-doped layer 415. Aportion of the material layer for forming the upper n-doped layer 415may be exposed by removing a portion of the lower p-doped layer 414material layer and a portion of the quantum well layer 416 material. Theremoving of such material layers may form the upper n-doped layer 415having a stepped shape as illustrated in FIG. 4. A distance in thethickness direction from the lower p-doped layer 414 to a commonreference such as the display substrate 401, may be smaller than thatfrom the upper n-doped layer 415 to define the step difference. Thesecond contact electrode 412 may be under the exposed portion of then-doped layer 415.

Since the step difference of the p-n diode 413 corresponding to theheight difference between the first wiring line 402 and the secondwiring line 405 is formed below the p-n diode 413 as described above,the LED 410 is horizontally arranged with respect to a plane in whichthe display substrate 401 is arranged (e.g., a plane defined by theX-direction and the Y-direction, referring to FIG. 1), and the LED 410may be relatively easily connected to the first wiring line 402 and thesecond wiring line 405.

Referring to FIG. 3, to improve a contact characteristic therebetween,the LED 410 may be electrically connected to the wiring lines in atleast two regions of the LED 410. In an embodiment, for example, the LED410 in FIG. 4 and the first wiring line 402 may form a first contactpoint (refer to 321 in FIG. 3) in plurality respectively at first andthird corners of the LED 410. The LED 410 and the second wiring line 405may form a second contact point (refer to 322 of FIG. 3) in pluralityrespectively at the second and fourth corners of the LED 410. A contactpoint may be defined as a location in the top plan view at which the LEDand the wiring line and contact each other. In FIG. 4, for example, thefirst contact electrode 411 and the first wiring line 402 form a firstcontact point at a location of contact therebetween, and the secondcontact electrode 412 and the second wiring line 405 form a secondcontact point at a location of contact therebetween.

A sealing layer 409 (refer to 205 in FIG. 3) may be over the displaysubstrate 401. The sealing layer 409 includes at least one inorganiclayer. The sealing layer 409 as a discrete element may individuallycover the LED 410 arranged in each pixel area PA.

FIG. 5 is an enlarged top plan view of another embodiment of portion Aof the display device in FIG. 1 according to the invention.

Referring to FIG. 5, a plurality of pixel areas PA may defined ordisposed on a display substrate 501. A light-emitting element such as anLED may be in the pixel area PA. A separation area SA may be betweenadjacent pixel areas PA.

The separation area SA includes a first separation area SA1 lengthwiseextending in an X-direction and a second separation area SA2 lengthwiseextending in a Y-direction. A plurality of through holes 502 may be inthe separation area SA. The through holes 502 may lengthwise extend in adirection in which the display substrate 501 is bent, curved or rolled.The through holes 502 collectively include a first through hole 503 inthe first separation area SA1 and a second through hole 504 in thesecond separation area SA2. The first and second through holes 503 and504 may be provided in plurality within the separation area SA.

A plurality of wiring lines 510 connected to an LED (not shown) may beon the display substrate 501. The wiring lines 510 collectively includea first wiring line 511 and a second wiring line 512. As describedabove, the first wiring line 511 and the second wiring line 512 may bedisposed on or in different insulating layers (not shown). The LED mayemit light when electric signals applied to the first wiring line 511and the second wiring line 512, respectively.

The first wiring line 511 may lengthwise extend over a plurality ofpixel areas PA spaced apart in an X-direction of the display substrate501. The first wiring line 511 may have at least a curve. In anembodiment, the first wiring line 511 may have a zigzag shape in the topplan view. The first wiring line 511 having the zigzag shape does notoverlap the plurality of through holes 502. The first wiring line 511and/or the second wiring line 512 may be defined by an entirely planarportion which is not spaced apart from an underlying layer in athickness direction of the display device, but the invention is notlimited thereto.

The second wiring line 512 may lengthwise extend over a plurality ofpixel areas PA spaced apart in a Y-direction of the display substrate501. The second wiring line 512 may have a zigzag shape. The secondwiring line 512 having the zigzag shape does not overlap the pluralityof through holes 502.

In an embodiment, the first wiring line 511 may cross the second wiringline 512.

In another embodiment, the first and second wiring lines 511 and 512 maybe electrically connected to an LED via contact holes (not shown). In anembodiment of manufacturing a display device, the contact holes may beformed by removing portions of the insulating layers above, below and/orbetween different-layer wiring lines.

FIG. 6 is an enlarged top plan view of an embodiment of a region of adisplay substrate of a display device according to the invention, FIG. 7is an exploded perspective view of a wiring line and an LED in an islandarea of FIG. 6, and FIG. 8 is a cross-sectional view illustrating anembodiment of a connection between the wiring line and the LED of FIG.7. In an embodiment, the view of FIG. 6 may correspond to portion A inFIG. 1.

Referring to FIGS. 6 to 8, a plurality of island areas IA may bedisposed on a display substrate 601. The island area IA may be an areaat which the wiring line 610 may directly contact the display substrate601.

A separation area SA may be between adjacent island areas IA. Theseparation area SA includes a first separation area SA1 lengthwiseextending in an X-direction and a second separation area SA2 lengthwiseextending in a Y-direction. A plurality of through holes 602 may be inthe separation area SA. The through holes 602 may each lengthwise extendin a direction in which the display substrate 601 is bent, curved orrolled. The through holes 602 collectively include a first through hole603 in the first separation area SA1 and a second through hole 604 inthe second separation area SA2.

A through hole enlarged portion 605 may be defined at both of opposingends of a single one among the through holes 602. Each through holeenlarged portion 605 may be a region in which a size of the through holeis greater than at remaining regions of the same through hole. In anembodiment, each of the plurality of through holes 602 defines a widthperpendicular to the length thereof. The width of each through hole atboth of the opposing ends thereof is greater than a width of remainingportions of the each through hole. Since the through hole enlargedportions 605 are defined at both of the opposing ends of respectivethrough holes 602, the display substrate 601 may be bent, curved orrolled in the length direction of the through holes 602 more easily.

A plurality of wiring lines 610 may be disposed on the display substrate601. An LED 710 may be electrically connected to the wiring lines 610.The wiring lines 610 collectively include a first wiring line 611 and asecond wiring line 612. The first and second wiring lines 611 and 612may be provided in plurality. The LED 710 may generate and emit lightwhen electric signals applied to the first wiring line 611 and thesecond wiring line 612, respectively, are further applied to the LED710.

Unlike the wiring lines in the above-described embodiments, the firstwiring line 611 and the second wiring line 612 may lengthwise extend inthe same direction. The first and second wiring lines 611 and 612 mayhave a nanoribbon shape considering a shape thereof in the X-, Y- andZ-directions.

The first and second wiring lines 611 and 612 may each lengthwise extendover a plurality of island areas IA spaced apart from each other in aY-direction of the display substrate 601. In another embodiment, thefirst and second wiring lines 611 and 612 may each lengthwise extendover a plurality of island areas IA spaced apart from each other in anX-direction of the display substrate 601.

The first wiring line 611 may be adjacent to the second wiring line 612in the top plan view. A pair of first and second wiring lines 611 and612 may be overlapping a single island area IA. The island area IA maybe provided in plurality in a row of island areas (e.g., in theX-direction of FIG. 6) or in a column of island areas (e.g., in theY-direction of FIG. 6). In an embodiment, a pair of first and secondwiring lines 611 and 612 may overlap a single column of island areas asshown in FIG. 6. In similar fashion, although not shown, a pair of firstand second wiring lines 611 and 612 may overlap a single row of islandareas.

In an embodiment, to implement a display device having a stretchablestructure, a portion of the wiring line 610 may be bent in the vertical(e.g., thickness) direction of the display substrate 601.

The first wiring line 611 includes a planar portion 613 provided inplurality and a first curved portion 614 connecting adjacent firstplanar portions 613 to each other. The first curved portion 614 may bedefined by the first planar portion 613 bent in the upper direction ofthe display substrate 601 (e.g., the Z-direction). In an embodiment thefirst curved portion 614 is common to a pair of first planar portions613 adjacent to each other along a length of the first wiring line 611.Where each of the planar portions 613 has a first and a second end whichis opposite to the first end, the common first curved portion 614extends from a first end of one of the pair of the adjacent first planarportions 613 and a second end of the other one of the pair of theadjacent first planar portions 613. In an embodiment, the first curvedportion 614 may have an arch shape in cross-section showing thethickness direction of the display substrate 601. The first curvedportion 614 may have elasticity.

Referring to FIGS. 6 and 7, the first planar portion 613 and the firstcurved portion 614 may be alternately arranged in a Y-direction of thedisplay substrate 601. The first planar portion 613 and the first curvedportion 614 may be formed as one body to define a single, unitary firstwiring line 611. That is, one of the first planar portion 613 and thecurved portion 614 may be extended to define the other one of the firstplanar portion 613 and the curved portion 614. The first planar portion613 may be bonded to the island area IA of the display substrate 601.The first planar portion 613 and the display substrate 601 may form afirst contact point 615 by an interface or a contact therebetween. Thefirst curved portion 614 may be located between a plurality of islandareas IA spaced apart from each other in the Y-direction of the displaysubstrate 601. Opposing ends of the first curved portion 614 may berespectively disposed in adjacent island areas IA spaced apart from eachother.

The second wiring line 612 includes a second planar portion 616 providedin plurality and a second curved portion 617 connecting adjacent secondplanar portions 616 to each other. The second curved portion 617 may bedefined by the second planar portion 616 bent in the upper direction ofthe display substrate 601 (e.g., the Z-direction). In an embodiment, thesecond curved portion 617 may have an arch shape in cross-section. Thesecond curved portion 617 may have elasticity.

Referring to FIGS. 6 and 7, the second planar portion 616 and the secondcurved portion 617 may be alternately arranged in the Y-direction of thedisplay substrate 601 and may be formed as one body to define a single,unitary second wiring line 612. That is, one of the second planarportion 616 and the second curved portion 617 may be extended to definethe other one of second planar portion 616 and the second curved portion617. The second planar portion 616 may be bonded to the island area IAof the display substrate 601. The second planar portion 616 and thedisplay substrate 601 may form a second contact point 618 by aninterface or a contact therebetween. The second curved portion 617 maybe located between a plurality of island areas IA spaced apart from eachother in the Y-direction of the display substrate 601. Opposing ends ofthe second curved portion 617 may be respectively disposed in adjacentisland areas IA spaced apart from each other.

A single LED 710 may be commonly disposed on the first curved portion614 and the second curved portion 617 of different wiring lines. Withrespect to the first curved portion 614 and the second curved portion617, a region of the display substrate 601 at which the LED 710 iselectrically connected to the wiring lines may correspond to a pixelarea PA.

The LED 710 includes a first contact electrode 711, a second contactelectrode 712, and a p-n diode 713 between the first and second contactelectrodes 711 and 712.

The p-n diode 713 includes a p-doped layer 714, an n-doped layer 715,and at least one quantum well layer 716 between the p-doped layer 714and the n-doped layer 715.

The LED 710 may be a horizontal LED.

Both the first contact electrode 711 and the second contact electrode712 may face the same direction relative to the p-n diode 713.Specifically, the first and second contact electrodes 711 and 712 mayboth be respectively arranged toward the first and second wiring lines611 and 612 among sides of the LED 710. The first and second contactelectrodes 711 and 712 may collectively include conductive paste or aconductive ball.

The p-doped layer 714 and the n-doped layer 715 may be arranged in thehorizontal direction of the display substrate 601. The first contactelectrode 711 may be under the p-doped layer 714, and the second contactelectrode 712 may be under the n-doped layer 715.

The first contact electrode 711 may be electrically connected to thefirst curved portion 614, and the second contact electrode 712 may beelectrically connected to the second curved portion 617. The connectionof the first curved portion 614 and the first contact electrode 711, andthe connection of the second curved portion 617 and the second contactelectrode 712 may be performed by laser welding or ultrasonic welding.

Since the LED 710 is electrically connected to the wiring lines at thefirst and second curved portions 614 and 617 as described above, thefirst and second curved portions 614 and 617 may absorb impact that mayoccur during a transfer process of the LED 710 in manufacturing adisplay device.

FIGS. 9A to 9D are cross-sectional views sequentially illustrating anembodiment of a process of manufacturing a wiring line having a curvedportion according to the invention.

Referring to FIG. 9A, a base layer 902 is formed on a display substrate901. Any material may be used for the base layer 902 as long as thematerial may be deformed or melted by applying predetermined heat. In anembodiment, the base layer 902 may be a polymer. In another embodiment,the base layer 902 may be a material that may be melted by using asolvent. The through hole described in FIG. 6 may be formed in a displaysubstrate 901 in advance.

Referring to FIG. 9B, the base layer 902 is patterned such as by aphotolithography method. A patterned base layer 903 may have the samepattern as the pattern of a wiring line. In FIG. 9B, patterns of thepatterned base layer 903 are spaced apart from each other in thehorizontal direction along the display substrate 901 by recesses definedtherebetween. The horizontal direction in FIG. 9B may correspond to alength direction of a wiring line to be formed thereon.

Referring to FIG. 9C, a wiring line 904 is formed on the patterned baselayer 903 to extend across the patterns and recesses arranged in thehorizontal direction. The wiring line 904 may include a metallicmaterial having conductivity. The wiring line 904 may be deposited onthe patterned base layer 903.

With the wiring line 904 formed on the patterned base layer 903 asdescribed above, the underlying patterned base layer 903 may be removedby applying predetermined heat thereto. In another embodiment, with thewiring line 904 formed on the patterned base layer 903 as describedabove, the underlying patterned base layer 903 may be removed by using asolvent.

Referring to FIG. 9D, by removing of the patterned base layer 903, thewiring line 904 remains on the display substrate 901, the wiring line904 having a plurality of planar portions 905 and a curved portion 906connecting adjacent planar portions 905 to each other is formed on thedisplay substrate 901. The planar portion 905 may be bonded on thedisplay substrate 901. The curved portion 906 may be spaced apart in theupper (e.g., thickness) direction of the display substrate 901. Since aspace S is formed between the display substrate 901 and the curvedportion 906, the space S may absorb impact during a transfer process ofan LED in manufacturing a display device.

As described above, one or more embodiment of a display device accordingto the invention may improve connection reliability between an LED and awiring line which supplies signals or power to the LED.

What is claimed is:
 1. A display apparatus, comprising: a displaysubstrate including: a plurality of pixel areas separated from eachother, and a plurality of through holes separated from each other; aplurality of light-emitting diodes arranged in the pixel areas; and awiring line contacting the plurality of light-emitting diodes, thewiring line comprising a plurality of planar portions and a plurality ofcurved portions, wherein the wiring line extends in one direction of thedisplay substrate, a first light-emitting diode of the plurality oflight-emitting diodes is connected to a first one of the curvedportions, and a second light-emitting diode of the plurality oflight-emitting diodes is connected to a second one of the curvedportions, and the first light-emitting diode and the secondlight-emitting diode are electrically connected to each other.
 2. Thedisplay apparatus of claim 1, wherein each of the plurality of planarportions contacts the display substrate, and each of the curved portionsconnects adjacent planar portions to each other.
 3. The displayapparatus of claim 2, wherein the plurality of planar portions and theplurality of curved portions are alternately arranged, and each of thelight-emitting diodes is connected to each of the curved portions. 4.The display apparatus of claim 2, wherein each of the curved portionsprotrudes upward from the display substrate from each end of adjacentplanar portions so as to be spaced apart from the display substrate. 5.The display apparatus of claim 2, wherein the display substratecomprises a plurality of island areas spaced apart from each other, andeach of the plurality planar portions contacts the island areas.
 6. Thedisplay apparatus of claim 2, wherein the wiring line is provided inplural comprising a first wiring line and a second wiring line which isspaced apart from the first wiring line, the first wiring line comprisesa plurality of first planar portions and a plurality of first curvedportions which connect adjacent first planar portions to each other, thesecond wiring line comprises a plurality of second planar portions and aplurality of second curved portions which connect adjacent second planarportions to each other, and each of the first wiring line and the secondwiring line is connected to a same light-emitting diode in one of theplurality of pixel areas.
 7. The display apparatus of claim 6, whereineach of the first wiring line and the second wiring line extends in thesame direction.
 8. The display apparatus of claim 6, wherein thelight-emitting diode comprises: a first contact electrode; a secondcontact electrode; and a p-n diode between the first contact electrodeand the second contact electrode, wherein the first contact electrode iselectrically connected to the first wiring line, and the second contactelectrode is electrically connected to the second wiring line.
 9. Thedisplay apparatus of claim 1, wherein the wiring line continuouslypasses through the plurality of through holes and extends in onedirection of the display substrate.
 10. The display apparatus of claim1, wherein the planar portions do not overlap the through holes in aplan view of the display substrate.
 11. The display apparatus of claim1, wherein at least a portion of the curved portions overlaps thethrough holes in a plan view of the display substrate.
 12. The displayapparatus of claim 1, wherein the display substrate is bendable,curvable, or rollable in a direction, and each of the plurality ofthrough holes has a length that extends in the direction in which thedisplay substrate is bent, curved or rolled.
 13. The display apparatusof claim 12, wherein a width of opposite ends of the each through holeis greater than a width of another portion of the through hole.